A keyboard is widely used as a basic input device of a computer. Generally, a keyboard includes a key top and an electric switch, and has a stroke which indicates the degree of depression in order to generate “click” feeling at the time of input. A user feels as if the load is reduced at the point when the switch is turned on. This generates “click” feeling and the user can recognize the key is actually input.
However, the shock at the time of pressing a key and prolonged use of a keyboard poses load on the fingers and hands of the user. Recently, many users who use computers in everyday work suffer from tendovaginitis.